Abstract: As a typical new organizational form in the era of Internet economy, platform enterprises have shown obvious advantages in promoting knowledge sharing and value creation, but there are few researches on the mechanism of platform enterprises promoting knowledge sharing and value co-creation from the perspective of knowledge governance. Therefore, in the context of platform, this paper analyzes the impact mechanism of knowledge governance on value co-creation, and explores the mediating role of knowledge sharing between knowledge governance and value co-creation. Through the empirical test of 220 questionnaires of some platform enterprises and their users in China, it is found that market and hierarchical knowledge governance have a positive impact on value co-creation and knowledge sharing, while social knowledge governance has no significant impact on value co creation and knowledge sharing; knowledge sharing plays a mediating role in the relationship between market and hierarchical knowledge governance and value co-creation, respectively. It does not play a mediating role in the relationship between social knowledge governance and value co-creation.